患牙有垂直的叩痛,通常是什么病的诊断依据
A.根尖周炎
B.牙龈炎
C.牙周炎
D.牙髓炎
E.以上疾病均可出现垂直叩痛
参考答案:A
The boy on the playground ____ be Tom, because he saw him in the library just now.
A.must
B.can't
C.can
D.might
近松剧本《国姓爷合战》的主人公是以谁为原型的?()
A、郑芝龙
B、郑成功
C、郑经
D、郑光祖